Parasiticidal formulation for animals and a method of making this formulation

ABSTRACT

A formulation for treating and preventing parasite infestations in horses, dogs, cats, and other animals is provided. This formulation includes a mixture of an edible non-aqueous liquid, a thickening agent, an agent effective against nematodes and obligate parasitic flies and a cestocidal agent, wherein the cestocidal agent is pyrantel, morantel, any salt thereof, or any combination thereof. Preferably, the agent effective against nematodes and obligate parasitic flies is an avermectin, a milbemycin or any combination thereof. Another aspect of the present invention is a method of making this parasiticidal formulation. A further aspect of the present invention is a method for administering the parasiticidal formulation of the present invention to an animal in the form of a paste.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

BACKGROUND OF THE INVENTION

The present invention relates to a formulation for treating, controllingand preventing parasitic worm infestations and a method for making theformulation. More specifically, the present invention relates to acombination roundworm and tapeworm parasiticide for use in horses andhousehold pets.

Several types of parasites, including cestodes, nematodes and obligateparasitic insects, particularly flies, commonly plague horses, dogs andcats. Cestodes are flatworms and include, for example, tapeworms, whilenematodes are roundworms. Avermectins and milbemycins are nematocidalagents commonly used in the treatment and control of parasitic roundworminfestations in equines, including domestic horses, donkeys, mules andzebras, as well as in companion animals, namely cats and dogs. Theseagents are also effective against obligate parasitic flies. Contrary topopular belief among animal owners, however, these agents areineffective against tapeworm infestations. Rather, tapeworm infestationsmust be controlled and treated by a cestocidal agent.

Studies have shown that misinformation about tapeworm treatment andcontrol is common among horse owners. Many horse owners evidentlybelieve that ivermectin, an avermectin used for treating and controllingroundworm infestations, is effective in controlling tapeworminfestations as well. This misinformation may account for a rise in theprevalence of certain tapeworms. A particular equine tapeworm whoseprevalence is on the rise is Anoplocephala perfoliata.

Tapeworms are pervasive parasites that appear to infect at least half ofall mature horses. Post-mortem studies have shown that, in general, atleast 50% of mature horses in many populations are infected with A.perfoliata. A. perfoliata is a type of tapeworm that can infect alltypes of equine animals. Adult A. perfoliata attach to the posteriorregions of the equine intestinal tract. The highest concentration is inthe cecal wall but a fair amount attach to the terminal ilium andventral colon as well. The greatest concentration of A. perfoliata, andthus the greatest associated damage, occurs at the ileocecal junction.A. perfoliata infestation increases the incidence of spasmodic colon andileal impaction in horses. Tapeworms also have been implicated as acause of cecal and ileocecal intussusceptions in young horses. Thelatter conditions are potentially fatal and can be remedied only bycomplicated and expensive abdominal surgery.

There are only a few classes of drugs which are effective in thetreatment, control and prevention of tapeworm infestations. Among theseclasses are praziquantel, pyrantel and morantel compounds. Parasiticidalformulations have been disclosed which contain praziquantel combinedwith a variety of roundworm controlling agents. One such formulation isdisclosed in U.S. Pat. No. 5,824,653 to Beuvry et al. The compoundswhich result from these combinations, however, may be dangerous aspraziquantel has been shown to be toxic at levels other than lowdosages. Additionally, praziquantel purportedly is bitter to tastemaking it unpalatable and thus undesirable in ingestable formulations,for example, pastes.

Pyrantel and morantel compounds are currently believed by those skilledin the art to offer an inadequate substitute to praziquantel in thetreatment and control of tapeworm infestations. Pyrantel salts generallyeither are only partially effective against tapeworms at their labeldosages (e.g., pyrantel pamoate) or must be administered in dailyregimes (e.g., pyrantel tartrate). Further, pyrantel pamoate offers alow suspended solids content when in paste form, the highest percentageencountered being about 43.95% weight per weight (w/w). A paste with alow suspended solids content contains less active ingredient per unitthan a paste with a higher suspended solids content. Therefore, a highervolume of paste must be delivered to the animal in order to achieve thesame therapeutic effect.

Accordingly, there remains a need in the veterinary industry for acombination parasiticidal formulation containing both a cestocidal agentand an agent effective against nematodes and obligate parasitic fliesthat is less toxic than formulations containing praziquantel. Further, apalatable combination parasiticide is needed for administration iningestable forms. The primary objective of this invention is to meetthese needs.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide aparasiticidal formulation that contains at least one agent effectiveagainst nematodes and obligate parasitic flies and at least one agenteffective against cestodes so as to broaden the formulation's spectrumof parasite protection.

It is another object of the present invention to provide a combinationparasiticidal formulation containing at least one agent that iseffective against nematodes and obligate parasitic flies and at leastone agent that is effective against cestodes which is less toxic thanprior formulations which include praziquantel.

A further object of the present invention is to provide a palatableparasiticidal formulation that contains at least one agent that iseffective against nematodes and obligate parasitic flies and at leastone agent that is effective against cestodes which may be administeredas a paste.

Still another object of the present invention is to provide a method ofmaking a parasiticidal formulation that achieves the foregoing objects.

Yet another object of the present invention is to provide a method foradministering a parasiticidal formulation that achieves the foregoingobjects.

According to the present invention, the foregoing and other objects areachieved by a parasiticidal formulation that includes a mixture of anedible non-aqueous liquid, a thickening agent, an agent effectiveagainst nematodes and obligate parasitic flies and an agent effectiveagainst cestodes, wherein the cestocidal agent is pyrantel, morantel,any salt thereof, or any combination thereof. Preferably, the agenteffective against nematodes and obligate parasitic flies is anavermectin, a milbemycin, a derivative thereof, or any combinationthereof. Another aspect of the present invention is a method of makingthis parasiticidal formulation. This method includes mixing theabove-mentioned components. A further aspect of the present invention isa method for administering the parasiticidal formulation of the presentinvention to an animal. This method of administration includes providingthe parasiticidal formulation described above in the form of a paste andadministering it to an animal for ingestion.

Additional objects of the invention, together with the advantages andnovel features appurtenant thereto, will be set forth in part in thedescription which follows, and in part will become apparent to thoseskilled in the art upon examination of the following, or may be learnedfrom the practice of the invention. The objects and advantages of theinvention may be realized and attained by means of the instrumentalitiesand combinations particularly pointed out in the appended claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The parasiticidal formulation of the present invention is an effectiveingestable formulation for the treatment and control of cestode,nematode and obligate parasitic fly infestations in equine and companionanimals. Such animals include, but are not limited to, horses, donkeys,mules, zebras, dogs and cats. The formulation includes an edible,non-aqueous liquid, a thickening agent, an agent for treating andcontrolling roundworm and obligate parasitic fly infestations and acestocidal agent for treating and controlling tapeworm infestations.This mixture provides a unique formulation in which the agent effectiveagainst nematodes and obligate parasitic flies is allowed to dissolvesubstantially into solution while the cestocidal agent remains generallysuspended. Thus, the system allows for delivery of two differentparasiticidal agents in two different physical states simultaneously ina single oral formulation.

The cestocidal agent of the present invention includes pyrantel,morantel, any salt of pyrantel or morantel, or any combination thereof.These compounds offer advantages over praziquantel in the control andtreatment of tapeworm infestations in that they have a higher dosagesafety margin than praziquantel. Pyrantel pamoate, a salt of pyrantel,for example, should present little to no adverse reaction when ingestedby horses in a concentration equivalent to two to five times the labelrecommended dosage. Further, pyrantels are desirable because horseowners are familiar with this group of compounds. Additionally, pyranteland morantel are more palatable than praziquantel as these compounds donot share the bitter taste associated with praziquantel.

Preferably, the cestocidal agent of the present invention is a salt ofpyrantel. Pyrantel salts that may be used in the formulation of thepresent invention include, but are not limited to, pyrantel pamoate,pyrantel tartrate or any combination thereof. Preferably, the cestocidalagent of the present invention is pyrantel pamoate. Pyrantel pamoate, atsufficiently high dosages, eliminates and controls infestations by avariety of tapeworms, including Anoplocephala perfoliata.

Pyrantel pamoate usually is classified as a nematocidal agent ratherthan a cestocidal agent at its recommended label dosage of about 6.6milligrams per kilogram of animal. At this dosage, pyrantel pamoate hasonly partial activity in the treatment and control of tapeworminfestations. Effectiveness percentages from about 65% to 100% againstcestode infestations have been shown with paste formulations, theaverage being about 85% efficacy. However, at about twice the labelrecommended dosage or higher, pyrantel pamoate exhibits tapewormcontrolling activity unattainable by many cestocidal compounds at anydosage. It has been observed that at an elevated dosage of about twotimes the label recommended dosage, or about 13.2 milligrams perkilogram of animal, pyrantel pamoate exhibits between about 93% and97.8% efficacy in horses infected with A. perfoliata. At an elevateddosage of about three times the label recommended dosage, or about 19.8milligrams per kilogram of animal, pyrantel pamoate is about 100%effective in treating cestode infestations. Consequently, theparasiticidal formulation of the present invention includesconcentrations of pyrantel pamoate at about two to three times thedosage recommended for treatment and control of roundworm infestations.

When the cestocidal agent chosen is pyrantel pamoate, the formulation ofthe present invention preferably may include about 40-75% w/w pyrantelpamoate (a total of about 14-26% w/w pyrantel in the formulation). Morepreferably, the formulation of the present invention may include about50-65% w/w pyrantel pamoate (a total of about 17-23% w/w pyrantel in theformulation). Formulations containing other cestocidal agents besidespyrantel pamoate are also contemplated by this invention, as discussedabove. If a different pyrantel compound is used, preferably theformulation would contain pyrantel in an amount similar to the amountsdiscussed above.

The agents which are effective against nematodes and obligate parasiticflies that may be used in the formulation of the present inventioninclude, but are not limited to, avermectins, milbemycins, anyderivative thereof, or any combination thereof. Avermectins that may beused in the formulation of the present invention include, but are notlimited to, abamectin, doramectin, eprinomectin, ivermectin, moxidectin,selamectin, or any combination thereof. These agents are most effectivewhen substantially dissolved in solution, i.e., when at least about 90%of the agent present is dissolved. Thus, it is preferred that theseagents be combined with a solvent before being administered to ananimal. Preferably the agent used in the formulation of the presentinvention is ivermectin. Ivermectin kills a variety of roundwormsincluding stomach worms, intestinal worms, lungworms, barber's poleworms, lice and mites, as well as bots and grubs of obligate parasiticflies.

When the agent chosen is ivermectin, the formulation of the presentinvention preferably may include about 0.10-10% w/w ivermectin. Morepreferably, the formulation of the present invention may include about0.25-0.35% w/w ivermectin.

As noted, cestocidal agents and agents effective against nematodes andobligate parasitic flies each provide protection against differentspecies of parasites. Thus, when combined in a single parasiticidalformulation, the formulation provides protection against a broaderspectrum of parasites than a formulation containing either parasiticidalagent alone. The formulation of the present invention preferably mayinclude a total of about 45-70% w/w parasiticidal agent, achieved bycombining an agent effective against nematodes and obligate parasiticflies and a cestocidal agent. More preferably, the formulation of thepresent invention includes about 50-60% w/w parasiticidal agents.

When using ivermectin and pyrantel pamoate in combination, theparasiticidal formulation of the present invention preferably mayinclude about 0.2-1.0% w/w ivermectin and about 45-65% w/w pyrantelpamoate. More preferably, the formulation of the present invention mayinclude about 0.2-0.5% w/w ivermectin and about 50-60% w/w pyrantelpamoate.

The edible, non-aqueous liquid that may be used in the formulation ofthe present invention includes, but is not limited to, edible glycolpolymers, edible oils, or any combination thereof. Edible glycolpolymers that may be used in the formulation of the present inventioninclude, but are not limited to, propylene glycol, polyethylene glycol,glycerine (glycerol), glycerol formal, or any combination thereof.Edible oils that may be used in the formulation of the present inventioninclude, but are not limited to, Arachis oil (peanut oil), polyoxylcastor oils, soybean oil, or any combination thereof. Preferably, theedible, non-aqueous liquid is propylene glycol.

The edible, non-aqueous liquid preferably is present in theparasiticidal formulation of the present invention in an amounteffective, in combination with the thickening agent, for substantiallydissolving a therapeutic amount of one or more agents effective againstnematodes and obligate parasitic flies while allowing one or morecestocidal agents to remain generally suspended. The agents effectiveagainst nematodes and obligate parasitic flies are substantiallydissolved in solution when at least about 90% of the agent present isdissolved. Cestocidal agents are generally suspended when less thanabout 10% of the agent present is dissolved. The formulation of thepresent invention preferably may include a total of about 40-50% w/wedible, non-aqueous liquid. More preferably, the formulation of thepresent invention may include about 42-46% w/w edible, non-aqueousliquid.

The thickening agent that may be used in the formulation of the presentinvention includes, but is not limited to, carbomers, cornstarch,polyethylene, polyvinylpyrrolidones, edible clay, xanthan gum, or anycombination thereof. Preferably, the thickening agents are a carbomerand xanthan gum. A suitable carbomer is Carbomer 974P manufactured byB.F. Goodrich. The thickening agent preferably includes an amount thatis effective, in combination with the edible, non-aqueous liquid, tosubstantially dissolve a therapeutic amount of one or more agentseffective against nematodes and obligate parasitic flies (preferably atleast about 90% dissolved) while allowing one or more cestocidal agentsto remain generally suspended (preferably less than about 10%dissolved). The formulation of the present invention preferably mayinclude about 0.01-1.0% w/w thickening agent. More preferably, theformulation of the present invention may include about 0.09-65% w/wthickening agent.

The combination of an edible, non-aqueous liquid and a thickening agentto form the unique system of the present invention allows one or morecestocidal agents to dissolve substantially while allowing one or moreagents effective against nematodes and obligate parasitic flies toremain generally suspended. As a result, the system of the presentinvention allows for delivery of two different parasiticidal agents intwo different physical states simultaneously in a single oralformulation. The combination of the edible, non-aqueous liquid and thethickening agent also functions to transport one or more cestocidalagents and one or more agents effective against nematodes and obligateparasitic flies into an animal in the physical state in which each ismost effective so that the agents may interact therapeutically withparasites in the animal. In animals with no parasite infestations uponadministration, the combination of the edible, non-aqueous liquid andthe thickening agent functions to transport one or more cestocidalagents and one or more agents effective against nematodes and obligateparasitic flies into an animal in the physical state in which each ismost effective so that the animal is protected from subsequentinfestations by certain parasites.

Further, the formulation of the present invention allows for highersuspended solids content for some cestocidal agents than was foreseen asbeing possible from the prior art. For example, the formulation of thepresent invention allows for a paste containing pyrantel pamoate havinga suspended solids content of up to about 70% w/w, with a preferredconcentration of about 54.13% w/w. The highest concentration previouslyencountered in a paste containing pyrantel was about 43.95% w/w. Thehigher suspended solids content allows for a significantly smallervolume of paste to be administered, making it easier to deliver higherdosages of pyrantel than when previously available formulations areused.

As discussed above, cestocidal agents and agents effective againstnematodes and obligate parasitic flies each provide protection againstdifferent species of parasites. Thus, when a cestocidal agent and anagent effective against nematodes and obligate parasitic flies arecombined in a single parasiticidal formulation, the formulation providesprotection against a broader spectrum of parasites than a formulationcontaining either parasiticidal agent alone. The parasiticidalformulation of the present invention may be administered either to treatinfected animals or to prevent infestations in non-infected animals.Preferably, the formulation is administered once per month.

While the edible, non-aqueous liquid, thickening agent, cestocidal agentand agent effective against nematodes and obligate parasitic flies arethe only components necessary in the formulation of the presentinvention, a number of optional ingredients may be added to enhancecertain properties of the formulation. One such optional ingredient is apreservative which acts to preserve both parasiticidal agents in thephysical state in which they are most effective. Preservatives that maybe used in the formulation of the present invention include, but are notlimited to, methylparaben, propylparaben, or any combination thereof.Preferably, the formulation of the present invention includes acombination of methylparaben and propylparaben in a ratio ofapproximately 10:1 respectively. If a combination of methylparaben andpropylparaben is chosen as a preservative for the formulation, theparasiticidal formulation of the present invention preferably mayinclude about 0.15-0.25% w/w methylparaben and about 0.015-0.025% w/wpropylparaben. More preferably, the parasiticidal formulation of thepresent invention may include about 0.18% w/w methylparaben and about0.02% w/w propylparaben.

Another optional ingredient that may be included in the formulation ofthe present invention is an additional solvent for the agent effectiveagainst nematodes and obligate parasitic flies. Preferably this solventis water. Water may be present in a concentration ranging from about0-10% w/w depending upon the concentration of edible, non-aqueous liquidused. The total amount of solvent should be sufficient to dissolvesubstantially all of the agent effective against nematodes and obligateparasitic flies present in the formulation of the present inventionwhile allowing all of the cestocidal agent to remain generallysuspended.

One preferred formulation of the present invention includes pyrantelpamoate, ivermectin, xanthan gum, carbomer, methylparaben, propylparabenand propylene glycol. Another preferred formulation of the presentinvention includes pyrantel pamoate, ivermectin, xanthan gum, carbomerand propylene glycol. A highly preferred formulation of the presentinvention which includes a preservative is described in Example 1. Ahighly preferred formulation of the present invention which does notinclude a preservative is described in Example 2.

The parasiticidal formulation of the present invention is made bycombining an edible non-aqueous liquid, a thickening agent, an agenteffective against nematodes and obligate parasitic flies and acestocidal agent to form a mixture. Preferably, ivermectin and pyrantelpamoate may be used respectively. The order in which components areadded in making the formulation is not critical. The formulation mayoptionally be heated to between about 60° and 80° C., continuously orintermittently, during its preparation in order to dissolve the agenteffective against nematodes and obligate parasitic flies more quickly.This process can be scaled to make any desired quantity of theformulation.

One preferred method of making the parasiticidal formulation of thepresent invention includes placing a quantity of edible, non-aqueousliquid in a vessel and warming it to about 70° C. Next, a quantity of anagent effective against nematodes and obligate parasitic flies is added,and the resulting solution is cooled to room temperature. The cestocidalagent is then added and mixed with the solution for an effective periodof time. The cestocidal agent will not dissolve into solution butinstead will remain generally suspended throughout, i.e., less thanabout 10% will dissolve. A thickening agent is then added and mixed intothe solution until it dissolves substantially, i.e., until at least 90%of the thickening agent present is dissolved. Optionally, a preservativethen may be added and mixed into the solution until substantiallydissolved, i.e., until at least 90% of the preservative present isdissolved.

Preferably, the parasiticidal formulation of the present invention isadministered as a paste formulation to any equine or companion animal.It is particularly useful for domestic horses, donkeys, mules, zebras,cats and dogs. Preferably, the paste is ingested by the animal and isadministered in a dosage of about 65-75 milligrams per kilogram ofanimal once per month.

The following are examples of various parasiticidal formulations andmethods of making these formulations that are within the scope of thisinvention. These examples are not meant in any way to limit the scope ofthis invention.

EXAMPLE 1

Propylene glycol, in a quantity amounting to 44.17% w/w of the finalformulation, was added to a vessel and warmed to 70° C. Agitation began.With continued agitation, a quantity of ivermectin amounting to 0.29%w/w of the final formulation was added to the propylene glycol and mixedwith it until all of the ivermectin substantially dissolved. Theresulting solution was then cooled to room temperature. A quantity ofpyrantel pamoate amounting to 55.14% w/w of the final formulation(19.13% w/w of final formulation as pyrantel) was then added and mixedwith the solution. The pyrantel pamoate did not dissolve in the solutionbut instead remained generally suspended throughout. Next, a quantity ofxanthan gum amounting to 0.18% w/w of the final formulation was added tothe mixture. With continued agitation, Carbomer 974P was added to themixture in a quantity amounting to 0.02% w/w of the final formulation.Subsequently, methylparaben, in a quantity amounting to 0.18% w/w of thefinal formulation, was added to the mixture, followed by a quantity ofpropylparaben amounting to 0.02% w/w of the final formulation. Theresulting formulation is within the scope of the present invention andincludes two parasiticidal agents, each targeting different species ofparasites.

EXAMPLE 2

Propylene glycol, in a quantity amounting to 44.37% w/w of the finalformulation, was added to a vessel and warmed to 70° C. Agitation began.With continued agitation, a quantity of ivermectin amounting to 0.29%w/w of the final formulation was added to the propylene glycol and mixedwith it until all of the ivermectin substantially dissolved. Theresulting solution was then cooled to room temperature. A quantity ofpyrantel pamoate amounting to 55.14% w/w of the final formulation(19.13% w/w of final formulation as pyrantel) was then added and mixedwith the solution. The pyrantel pamoate did not dissolve in the solutionbut instead remained generally suspended throughout. With continuedagitation, a quantity of xanthan gum amounting to 0.18% w/w of the finalformulation was added to the mixture. Subsequently, carbomer 974P wasadded to the mixture in a quantity amounting to 0.02% w/w of the finalformulation. The resulting formulation is within the scope of thepresent invention and includes two parasiticidal agents, each targetingdifferent species of parasites.

EXAMPLE 3

Propylene glycol, in a quantity amounting to 30% w/w of the finalformulation, was added to a vessel and warmed to 70° C. Agitation began.With continued agitation, water in a quantity amounting to 7.285% w/w ofthe final formulation, was added to the propylene glycol to form asolution. Next, a quantity of ivermectin amounting to 0.325% w/w of thefinal formulation was added to the solution and mixed with it until allof the ivermectin substantially dissolved. The resulting solution wasthen cooled to room temperature. A quantity of pyrantel pamoateamounting to 61.74% w/w of the final formulation (21.42% w/w of finalformulation as pyrantel) was then added and mixed with the solution. Thepyrantel pamoate did not dissolve in the solution but instead remainedgenerally suspended throughout. Lastly, a quantity of xanthan gumamounting to 0.65% w/w of the final formulation was added to themixture. The resulting formulation is within the scope of the presentinvention and includes two parasiticidal agents, each targetingdifferent species of parasites.

EXAMPLE 4

Propylene glycol, in a quantity amounting to 28% w/w of the finalformulation, was added to a vessel and warmed to 70° C. Agitation began.With continued agitation, water, in a quantity amounting to 9.285% w/wof the final formulation, was added to the propylene glycol to form asolution. Next, ivermectin amounting to 0.325% w/w of the finalformulation was added to the solution and mixed with it until all of theivermectin substantially dissolved. The resulting solution was thencooled to room temperature. A quantity of pyrantel pamoate amounting to61.74% w/w of the final formulation (21.42% w/w of final formulation aspyrantel) was then added and mixed with the solution. The pyrantelpamoate did not dissolve in the solution but instead remained generallysuspended throughout. Lastly, a quantity of xanthan gum amounting to0.65% w/w of the final formulation was added to the mixture. Theresulting formulation is within the scope of the present invention andincludes two parasiticidal agents, each targeting different species ofparasites.

EXAMPLE 5

Propylene glycol, in a quantity amounting to 32.0% w/w of the finalformulation, was added to a vessel and warmed to 70° C. Agitation began.With continued agitation, water, in a quantity amounting to 5.285% w/wof the final formulation, was added to the propylene glycol to form asolution. Next, ivermectin amounting to 0.325% w/w of the finalformulation was added to the solution and mixed with it until all of theivermectin substantially dissolved. The resulting solution was thencooled to room temperature. A quantity of pyrantel pamoate amounting to61.74% w/w of the final formulation (21.42% w/w of final formulation aspyrantel) was then added and mixed with the solution. The pyrantelpamoate did not dissolve in the solution but instead remained generallysuspended throughout. Lastly, a quantity of xanthan gum amounting to0.65% w/w of the final formulation was added to the mixture. Theresulting formulation is within the scope of the present invention andincludes two parasiticidal agents, each targeting different species ofparasites.

EXAMPLE 6

Propylene glycol, in a quantity amounting to 37.836% w/w of the finalformulation, was added to a vessel and warmed to 70° C. Agitation began.With continued agitation, water, in a quantity amounting to 7.0% w/w ofthe final formulation, was added to the propylene glycol to form asolution. Next, ivermectin amounting to 0.284% w/w of the finalformulation was added to the solution and mixed with it until all of theivermectin substantially dissolved. The resulting solution was thencooled to room temperature. A quantity of pyrantel pamoate amounting to54.03% w/w of the final formulation (18.75% w/w of final formulation aspyrantel) was then added and mixed with the solution. The pyrantelpamoate did not dissolve in the solution but instead remained generallysuspended throughout. With continued agitation, a quantity of xanthangum amounting to 0.65% w/w of the final formulation was added to themixture. Lastly, Carbomer 974P was added to the mixture in a quantityamounting to 0.02% w/w of the final formulation. The resultingformulation is within the scope of the present invention and includestwo parasiticidal agents, each targeting different species of parasites.

EXAMPLE 7

Propylene glycol, in a quantity amounting to 44.806% w/w of the finalformulation, was added to a vessel and warmed to 70° C. Agitation began.With continued agitation, water, in a quantity amounting to 0.48% w/w ofthe final formulation, was added to the propylene glycol to form asolution. Next, ivermectin amounting to 0.284% w/w of the finalformulation was added to the solution and mixed with it until all of theivermectin substantially dissolved. The resulting solution was thencooled to room temperature. With continued agitation, a quantity ofpyrantel pamoate amounting to 54.03% w/w of the final formulation(18.75% w/w of final formulation as pyrantel) was then added and mixedwith the solution. The pyrantel pamoate did not dissolve in the solutionbut instead remained generally suspended throughout. Next, a quantity ofxanthan gum amounting to 0.2% w/w of the final formulation was added tothe mixture. Lastly, Carbomer 974P was added to the mixture in aquantity amounting to 0.2% w/w of the final formulation. The resultingformulation is within the scope of the present invention and includestwo parasiticidal agents, each targeting different species of parasites.

EXAMPLE 8

Propylene glycol, in a quantity amounting to 43.4% w/w of the finalformulation, was added to a vessel and warmed to 70° C. Agitation began.With continued agitation, a quantity of ivermectin amounting to 0.275%w/w of the final formulation was added to the propylene glycol and mixedwith it until all of the ivermectin substantially dissolved. Theresulting solution was then cooled to room temperature. A quantity ofpyrantel pamoate amounting to 56.17% w/w of the final formulation(19.49% w/w of final formulation as pyrantel) was then added and mixedwith the solution. The pyrantel pamoate did not dissolve in the solutionbut instead remained generally suspended throughout. With continuedagitation, a quantity of xanthan gum amounting to 0.097% w/w of thefinal formulation was added to the mixture. Lastly, Carbomer 974P wasadded to the mixture in a quantity amounting to 0.097% w/w of the finalformulation. The resulting formulation is within the scope of thepresent invention and includes two parasiticidal agents, each targetingdifferent species of parasites.

EXAMPLE 9

Propylene glycol, in a quantity amounting to 44.14% w/w of the finalformulation, was added to a vessel and warmed to 70° C. Agitation began.With continued agitation, a quantity of ivermectin amounting to 0.29%w/w of the final formulation was added to the propylene glycol and mixedwith it until all of the ivermectin substantially dissolved. Theresulting solution was then cooled to room temperature. A quantity ofpyrantel pamoate amounting to 55.17% w/w of the final formulation(19.14% w/w of final formulation as pyrantel) was then added and mixedwith the solution. The pyrantel pamoate did not dissolve in the solutionbut instead remained generally suspended throughout. Next, a quantity ofxanthan gum amounting to 0.1% w/w of the final formulation was added tothe mixture. With continued agitation, Carbomer 974P was added to themixture in a quantity amounting to 0.1% w/w of the final formulation.Subsequently, methylparaben, in a quantity amounting to 0.18% w/w of thefinal formulation, was added to the mixture, followed by a quantity ofpropylparaben amounting to 0.02% w/w of the final formulation. Theresulting formulation is within the scope of the present invention andincludes two parasiticidal agents, each targeting different species ofparasites.

EXAMPLE 10

Propylene glycol, in a quantity amounting to 49.705% w/w of the finalformulation, was added to a vessel and warmed to 70° C. Agitation began.With continued agitation, a quantity of ivermectin amounting to 0.235%w/w of the final formulation was added to the propylene glycol and mixedwith it until all of the ivermectin substantially dissolved. Theresulting solution was then cooled to room temperature. A quantity ofpyrantel pamoate amounting to 49.7% w/w of the final formulation (17.25%w/w of final formulation as pyrantel) was then added and mixed with thesolution. The pyrantel pamoate did not dissolve in the solution butinstead remained generally suspended throughout. Next, a quantity ofxanthan gum amounting to 0.135% w/w of the final formulation was addedto the mixture. With continued agitation, Carbomer 974P was added to themixture in a quantity amounting to 0.045% w/w of the final formulation.Subsequently, methylparaben, in a quantity amounting to 0.162% w/w ofthe final formulation, was added to the mixture, followed by a quantityof propylparaben amounting to 0.018% w/w of the final formulation. Theresulting formulation is within the scope of the present invention andincludes two parasiticidal agents, each targeting different species ofparasites.

EXAMPLE 11

Propylene glycol, in a quantity amounting to 38.199% w/w of the finalformulation, was added to a vessel and warmed to 70° C. Agitation began.With continued agitation, a quantity of sterile water in a quantityamounting to 6.0% w/w of the final formulation was added to thepropylene glycol to form a solution. Next, ivermectin amounting to0.261% w/w of the final formulation was added to the solution and mixedwith it until all of the ivermectin substantially dissolved. Theresulting solution was then cooled to room temperature. A quantity ofpyrantel pamoate amounting to 55.14% w/w of the final formulation(19.13% w/w of final formulation as pyrantel) was then added and mixedwith the solution. The pyrantel pamoate did not dissolve in the solutionbut instead remained generally suspended throughout. With continuedagitation, a quantity of xanthan gum amounting to 0.1% w/w of the finalformulation was added to the mixture. With continued agitation, aquantity of Carbomer 974P was added to the mixture in a quantityamounting to 0.1% w/w of the final formulation. Lastly, methylparaben,in a quantity amounting to 0.18% w/w of the final formulation, was addedto the mixture, followed by a quantity of propylparaben amounting to0.02% w/w of the final formulation. The resulting formulation is withinthe scope of the present invention and includes two parasiticidalagents, each targeting different species of parasites.

EXAMPLE 12

Propylene glycol, in a quantity amounting to 44.19% w/w of the finalformulation, was added to a vessel and warmed to 70° C. Agitation began.With continued agitation, a quantity of ivermectin amounting to 0.261%w/w of the final formulation was added to the propylene glycol and mixedwith it until all of the ivermectin substantially dissolved. Theresulting solution was then cooled to room temperature. A quantity ofpyrantel pamoate amounting to 55.14% w/w of the final formulation(19.13% w/w of final formulation as pyrantel) was then added and mixedwith the solution. The pyrantel pamoate did not dissolve in the solutionbut instead remained generally suspended throughout. Next, a quantity ofxanthan gum amounting to 0.15% w/w of the final formulation was added tothe mixture. With continued agitation, Carbomer 974P was added to themixture in a quantity amounting to 0.05% w/w of the final formulation.Lastly, methylparaben, in a quantity amounting to 0.18% w/w of the finalformulation, was added to the mixture, followed by a quantity ofpropylparaben amounting to 0.02% w/w of the final formulation. Theresulting formulation is within the scope of the present invention andincludes two parasiticidal agents, each targeting different species ofparasites.

From the foregoing, it will be seen that this invention is one that iswell adapted to attain all the ends and objects hereinabove set forthtogether with other advantages which are obvious and inherent to theformulation.

It will be understood that certain features and subcombinations are ofutility and may be employed without reference to other features andsubcombinations. This is contemplated by and is within the scope of theclaims.

Since many possible embodiments may be made of the invention withoutdeparting from the scope thereof, it is to be understood that all matterherein set forth is to be interpreted as illustrative and not in alimiting sense.

Having thus described my invention, I claim:
 1. A parasiticidalformulation, comprising the mixture of: an edible, non-aqueous liquidthat is an edible oil selected from the group consisting of Arachis oil,polyoxyl castor oil, soybean oil and any combination thereof; athickening agent; an agent effective against nematodes and obligateparasitic flies; and a cestocidal agent, wherein said cestocidal agentis selected from the group consisting of pyrantel, morantel, any saltthereof and any combination thereof.
 2. A parasiticidal formulation,comprising the mixture of: an edible, non-aqueous liquid that is anedible glycol polymer selected from the group consisting of propyleneglycol, polyethylene glycol, glycerine, glycerol formal and anycombination thereof, wherein said non-aqueous liquid is comprised ofabout 25-55% weight per weight propylene glycol; a thickening agent; anagent effective against nematodes and obligate parasitic flies; and acestocidal agent, wherein said cestocidal agent is selected from thegroup consisting of pyrantel, morantel, any salt thereof and anycombination thereof.
 3. A parasiticidal formulation, comprising themixture of: an edible, non-aqueous liquid; a thickening agent selectedfrom the group consisting of a carbomer, cornstarch, polyethylene, apolyvinylpyrrolidone, an edible clay, xanthan gum and any combinationthereof; an agent effective against nematodes and obligate parasiticflies; and a cestocidal agent, wherein said cestocidal agent is selectedfrom the group consisting of pyrantel, morantel, any salt thereof andany combination thereof.
 4. The formulation of claim 3, wherein saidthickening agent is comprised of a carbomer and xanthan gum.
 5. Theformulation of claim 4, wherein said formulation is comprised of about0.01-0.5% weight per weight carbomer and about 0.05-1.0% weight perweight xanthan gum.
 6. A parasiticidal formulation, comprising themixture of: an edible, non-aqueous liquid; a thickening agent; an agenteffective against nematodes and obligate parasitic flies; a cestocidalagent, wherein said cestocidal agent is selected from the groupconsisting of pyrantel, morantel, any salt thereof and any combinationthereof; and a preservative selected from the group consisting ofmethylparaben, propylparaben and any combination thereof.